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	<div id="winchm_template_title">GetShortField</div>
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	<div id="winchm_template_content"><div id="mainSection"><p>The <b>GetShortField</b> function reads the value of a member in a structure if its size is less than or equal to 8 bytes, or initializes a structure so it can be read later.  This function is not intended to be used directly; <a href="#Bookmark1130"><b>InitTypeRead</b></a> or <a href="#Bookmark1132"><b>InitTypeReadPhysical</b></a> and <a href="#Bookmark1123"><b>ReadField</b></a> should be used instead.</p>
<h2>Syntax</h2>
<div class="code"><span codelanguage="ManagedCPlusPlus"><table>
<tr>
<th>C++</th>
</tr>
<tr>
<td>
<pre>__inline ULONG64 GetShortField(
  _In_ ULONG64 TypeAddress,
  _In_ LPCSTR  Name,
  _In_ USHORT  StoreAddress
);</pre>
</td>
</tr>
</table></span></div>
<h2>Parameters</h2>
<dl>
<dt><i>TypeAddress</i> [in]</dt>
<dd>
<p>The meaning of this parameter depends on the value of <i>StoreAddress</i>.</p>
<p></p>
<dl>
<dt><a id="If_StoreAddress_is_non-zero_"></a><a id="if_storeaddress_is_non-zero_"></a><a id="IF_STOREADDRESS_IS_NON-ZERO_"></a>If <i>StoreAddress</i> is non-zero:</dt>
<dd>
<p>Specifies the address of the structure in the target's memory.  This address is used for subsequent calls when <i>StoreAddress</i> is zero. </p>
</dd>
<dt><a id="If_StoreAddress_is_zero_"></a><a id="if_storeaddress_is_zero_"></a><a id="IF_STOREADDRESS_IS_ZERO_"></a>If <i>StoreAddress</i> is zero:</dt>
<dd>
<p><i>TypeAddress</i> is ignored.  The value of <i>TypeAddress</i> from the last call when <i>StoreAddress</i> was non-zero is used to specify the address of the structure in the target's memory. </p>
</dd>
</dl>
</dd>
<dt><i>Name</i> [in]</dt>
<dd>
<p>The meaning of this parameter depends on the value of <i>StoreAddress</i>.</p>
<p></p>
<dl>
<dt><a id="If_StoreAddress_is_non-zero_"></a><a id="if_storeaddress_is_non-zero_"></a><a id="IF_STOREADDRESS_IS_NON-ZERO_"></a>If <i>StoreAddress</i> is non-zero:</dt>
<dd>
<p>Specifies the name of the type of the structure at <i>TypeAddress</i>.</p>
</dd>
<dt><a id="If_StoreAddress_is_zero_"></a><a id="if_storeaddress_is_zero_"></a><a id="IF_STOREADDRESS_IS_ZERO_"></a>If <i>StoreAddress</i> is zero:</dt>
<dd>
<p>Specifies the name of the member in the structure to read.  The address and type of the structure are remembered from a previous call to this function with <i>StoreAddress</i> not equal to zero.  Submembers can be specified by using a period-separated path, for example, "myfield.mysubfield". </p>
</dd>
</dl>
</dd>
<dt><i>StoreAddress</i> [in]</dt>
<dd>
<p>Specifies the mode of this function.</p>
<p></p>
<dl>
<dt><a id="If_StoreAddress_is_non-zero_"></a><a id="if_storeaddress_is_non-zero_"></a><a id="IF_STOREADDRESS_IS_NON-ZERO_"></a>If <i>StoreAddress</i> is non-zero:</dt>
<dd>
<p>Causes this function to initialize a structure for reading its members.  The address and type name for the structure is remembered.</p>
<p>If the bit value 0x2 is set in <i>StoreAddress</i>, the address <i>TypeAddress</i> is considered a physical address; otherwise, it is considered a virtual address. </p>
</dd>
<dt><a id="If_StoreAddress_is_zero_"></a><a id="if_storeaddress_is_zero_"></a><a id="IF_STOREADDRESS_IS_ZERO_"></a>If <i>StoreAddress</i> is zero:</dt>
<dd>
<p>Causes this function to read a member from a previously initialized structure. </p>
</dd>
</dl>
</dd>
</dl>
<h2>Return value</h2>
<table>
<tr>
<th>Return code</th>
<th>Description</th>
</tr>
<tr>
<td width="40%">
<dl>
<dt><b>If <i>StoreAddress</i> is non-zero:</b></dt>
</dl>
</td>
<td width="60%">
<p>If the function succeeds, it returns the value zero.  If the function fails because the caller passed a zero value as <i>TypeAddress</i>, it returns the value MEMORY_READ_ERROR (defined in Wdbgexts.h).  If the function fails for any other reason, it returns an <a href="#Bookmark1081"><b>IG_DUMP_SYMBOL_INFO error code</b></a>.</p>
</td>
</tr>
<tr>
<td width="40%">
<dl>
<dt><b>If <i>StoreAddress</i> is zero:</b></dt>
</dl>
</td>
<td width="60%">
<p>If the function succeeds, it returns the value of the specified field in the previously initialized structure.  The structure is the one initialized in a previous call to <b>GetShortField</b>.  The field is the one specified by the <i>Name</i> parameter of the current call to <b>GetShortField</b>. The return value is cast to ULONG64.  If the function fails, it returns the value zero. </p>
</td>
</tr>
</table>
<p> </p>
<h2>Remarks</h2>
<p>When <b>GetShortField</b> is called with a nonzero <i>StoreAddress</i> value, it initializes the structure located at the address specified by <i>TypeAddress</i>. Only one structure can be initialized at a time. If <b>GetShortField</b> is called more than once with a nonzero <i>StoreAddress</i> value, only the structure specified in the most recent call is initialized. When <b>GetShortField</b> is called with <i>StoreAddress</i> equal to zero, it accesses the most recently initialized structure, reads in that structure the field specified by <i>Name</i>, and returns the value of that field. </p>
<p>This function does not need to be called directly.  The macros <a href="#Bookmark1130"><b>InitTypeRead</b></a> and <a href="#Bookmark1132"><b>InitTypeReadPhysical</b></a> call this function with <i>StoreAddress</i> non-zero to prepare a structure for reading its members.  The macro <a href="#Bookmark1123"><b>ReadField</b></a> calls this function with <i>StoreAddress</i> (and <i>TypeAddress</i>) equal to zero, to read members from the structure.</p>
<div class="alert"><b>Note</b>    because this function stores the <i>TypeAddress</i> and <i>Name</i> by using static local variables, and because this function is defined in WdbgExts.h, the C pre-processor will create a new instance of this function for each DLL, and <i>TypeAddress</i> and <i>Name</i> will only be available within a single source file.  In other words, the structure must be initialized in the same source file from which the members are read.</div>
<div> </div>
<h2>Requirements</h2>
<table>
<tr>
<th width="30%">
<p>Target platform</p>
</th>
<td width="70%">
<dl>
<dt></dt>
</dl>
</td>
</tr>
<tr>
<th width="30%">
<p>Header</p>
</th>
<td width="70%">
<dl>
<dt>Wdbgexts.h (include Wdbgexts.h, Wdbgexts.h, or Dbgeng.h)</dt>
</dl>
</td>
</tr>
</table>
<h2><a id="see_also"></a>See also</h2>
<dl>
<dt><a href="#Bookmark1130"><b>InitTypeRead</b></a></dt>
<dt><a href="#Bookmark1132"><b>InitTypeReadPhysical</b></a></dt>
<dt><a href="#Bookmark1123"><b>ReadField</b></a></dt></dl></div></div>	
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